Diference between BCS(bachelor of computer science) and BCA(bachelor of computer applications)?

Both are one other the same, they will have same core curriculum. The name of degrees depends on the institute which offers these courses, both are eligible to enroll yourself in MCA (if you are looking to do it), there are also MCA courses for out of school (12th or PUC) students, which is a 5 years course offered by some institues, you may check out them too. Good luck.